Drive Control Device Motor Failure Detection via Mode Switching

Solution Overview

Problem

In drive control devices where a single control unit manages multiple drive sources, it is challenging to detect failures in individual motors due to shared encoder usage, leading to difficulties in identifying motor failures during operation.

Innovation Solution

The implementation of a drive control device with operation modes that allow for separate control of each motor, using a single PID control unit to generate a drive control signal and employing mode switching to isolate motors for failure detection, enabling detection of motor failures through abnormal output monitoring.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single control unit is used to control multiple drive sources, then device size and cost are reduced, but the ability to detect individual motor failures is compromised

Engineering Contradiction:

Improvedevice sizeVSAvoidfailure detection capability

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The system performs preliminary failure detection by switching to check modes before actual failure occurs. The control unit periodically switches each drive source to a check mode where it is driven independently, allowing the system to detect potential failures in advance while maintaining normal operation with multiple drive sources

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The control unit dynamically switches between normal mode (where multiple drive sources operate together) and check modes (where individual drive sources are tested separately). This dynamic switching allows the system to maintain cost-effectiveness while enabling failure detection through temporary operational state changes

Inventive Principle:

Principle #15Dynamics

2Device complexity

If a single control unit is used to control multiple drive sources, then device cost is reduced, but the ability to detect individual motor failures is compromised

Engineering Contradiction:

Improvedevice costVSAvoidfailure detection capability

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The system performs preliminary failure detection by switching to check modes before actual failure occurs. The control unit periodically switches each drive source to a check mode where it is driven independently, allowing the system to detect potential failures in advance while maintaining normal operation with multiple drive sources

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The control unit dynamically switches between normal mode (where multiple drive sources operate together) and check modes (where individual drive sources are tested separately). This dynamic switching allows the system to maintain cost-effectiveness while enabling failure detection through temporary operational state changes

Inventive Principle:

Principle #15Dynamics

3Stability of the object's composition

If multiple drive sources are used to drive a single output shaft, then vibration damping is improved, but the complexity of controlling each drive source increases

Engineering Contradiction:

Improvevibration damping propertyVSAvoidcontrol unit quantity

Core Design Contradiction:

Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The patent merges multiple control functions into a single control unit. This control unit is capable of controlling multiple drive sources simultaneously and switching between different operational modes (normal mode and check modes), thereby reducing the number of control units while maintaining the vibration damping benefits of multiple drive sources

Inventive Principle:

Principle #5Merging (Combining)

Data Source

PatentUS11442391B2Drive control device, driving device, sheet conveying device, and image forming apparatus

Publication Date: 2022.09.13 RICOH CO LTD

AI summary

A drive control device is configured to control a plurality of drive sources configured to drive a single output shaft. The drive control device includes a control unit configured to generate a single drive control signal and transmit the drive control signal to the plurality of drive sources. The drive control device has, as operation modes, a first mode for driving the plurality of drive sources and a second mode for driving a part of the plurality of drive sources.